Air Blower for Whirlpool

[AquaPNC]

Hey team,

Can I add an air blower to an in-ground whirlpool after construction? The spa equipment is within 8' of the whirlpool.


Thanks!

 

[ajw22]

No, a spa needs to be plumbed with separate air and water lines that are combined in a manifold at each spa jet.

You cannot connect a spa blower to a water line.

 

[1poolman1]

Hey team,

Can I add an air blower to an in-ground whirlpool after construction? The spa equipment is within 8' of the whirlpool.


Thanks!

Are these spa jets, or just returns? If jets, then you can add a blower to the air line that would be at the equipment pad. If only return lines, no.

 

[AquaPNC]

Are these spa jets, or just returns? If jets, then you can add a blower to the air line that would be at the equipment pad. If only return lines, no.

The current hot tub is basically the concrete shell with 8 high return lines. I'd read previously their is a way to accomplish this all be it a very complicated way, but I'm having a hard time remembering the method.

 

[1poolman1]

The current hot tub is basically the concrete shell with 8 high return lines. I'd read previously their is a way to accomplish this all be it a very complicated way, but I'm having a hard time remembering the method.

Is there an air-induction line (basically an open pipe) at the equipment pad? Are there air valves above each return?

 

[AquaPNC]

Is there an air-induction line (basically an open pipe) at the equipment pad? Are there air valves above each return?

No air valves around the return, we do have access to the plumbing which is about 6ft from the hot tub, but it is just the return line. I read previously it could be accomplished with a check valve and a blower addition 4ft above the waterline but the feedback has of sure varied and I don't want to even try if it isn't possible.

My biggest fear is having significantly more pressure on the nearest jet/return than the farthest. I don't have the knowledge of the hydraulics, I am a commercial pool remodel company who has built a handful of concrete pools locally, all be it successfully but for me this situation is unprecedented.

I appreciate the feedback.

 

[oldprophet]

No, a spa needs to be plumbed with separate air and water lines that are combined in a manifold at each spa jet.

You cannot connect a spa blower to a water line.

You can. You simply plum the air blower into the air line. I've done it many times. Depending on the location, adding a check valve might be necessary

 

[ajw22]

You can. You simply plum the air blower into the air line. I've done it many times. Depending on the location, adding a check valve might be necessary

What if there is no air line?

 

[JamesW]

If no air line, you might be able to add one of these to each return line and use a blower to inject air.

Can you show the jets and the equipment?

Waterway Plastics VENTURI TEE #7 ASSEMBLY | 210-3330

Waterway Plastics 210-3330 VENTURI TEE #7 ASSEMBLY

www.wildwestpoolsupplies.com

 

[JamesW]

Westlake Pipe & Fittings Products: 1½(2) x 1½ x ¾(1) Slip (SP) x Slip x Slip (SP) Pool Spa Venturi Tee

www.lascofittings.com

1½(2) x 1½ x ¾(1) Slip (SP) x Slip x Slip (SP) Pool Spa Venturi Tee
$19.34 USD

Product ID: 473210
Size: 1½(2) x 1½ x ¾(1)
Carton Quantity: 25
Code: 09/9B
Pallet Quantity: 1600
Cartons per Pallet: 64
Layer Quantity: 400
ASTM D-1784: Rigid Poly (Vinyl Chloride) (PVC) Compounds and Chlorinated Poly (Vinyl Chloride) (CPVC) Compounds.

 

[JamesW]

Venturi Tees - CMP

www.c-m-p.com

 

[AquaPNC]

Thanks James!

If it is possible we would love to be able to add this feature for the client. I told him I would find out if its possible so we appreciate your feedback!

 

[ajw22]

You need to run an air line parallel to the jet water line and install the Venturi Ts at each jet.

 

[JamesW]

Do you know what fittings are in the wall?

You can core drill out the existing fittings and install new venturi jet fittings and install an air line with a blower.

The returns look poorly balanced and undersized.

I would run a bigger line and design a more hydraulically balanced plumbing system.

I suspect that the suction is probably undersized as well.

Pipe Size and Flow Rates.​

You want to keep the water velocity below 6 ft/sec on the suction and below 8 ft/sec on the pressure side of the pump.[7]

Pipe Size	6 ft/sec	8 ft/sec
1.5"	38 GPM	51 GPM
2"	63 GPM	84 GPM
2.5	90 GPM	119 GPM
3.0"	138 GPM	184 GPM
4.0"	235 GPM	312 GPM

Equipment Pad Best Practices - Further Reading

www.troublefreepool.com

You need to know the flow per jet and multiply by the number of jets.

For example, 8 jets at 15 gpm per jet requires 120 gpm, which requires a 3" suction and I would use a 3" return as well.

 

[JamesW]

Maybe contact CMP and ask them to help you design a retrofit with their venturi jets as it will be tricky doing this after the concrete is already shot.

 

[JamesW]

The current hot tub is basically the concrete shell with 8 high return lines.

With 8 jets, you need a lot of flow to make the jets work correctly.

I would probably want an Intelliflo XF just for the jets and you will need at least a 3" suction line and 4 regular main drains or 2 big commercial unblockable main drains.

IntelliFloXF VSF Pump

Pentair IntelliFloXF VSF Pump - This innovative, variable speed & variable flow pool pump offers precision and savings for large and feature-rich pools.

www.pentair.com

https://www.pentair.com/content/dam/extranet/nam/pentair-pool/commercial/pumps/intelliflo-xf-vsf/intellifloxfvsf-pump-brochure-english.pdf

 

[oldprophet]

What if there is no air line?

There has to be an air line

 

[ajw22]

There has to be an air line

I don’t see an air line…

 

[oldprophet]

I don’t see an air line…

I'm sorry, I misunderstood the picture you sent. There are no venturi fittings in that picture of your spa and there are no air lines

 

[JamesW]

This was never designed correctly from the beginning.

What main drains are available and what size is the main drain line?

If you do not have enough main drain surface area and a 3" suction, it will probably not work unless you do some serious modification.